/* * mfd.c: driver for High Speed UART device of Intel Medfield platform * * Refer pxa.c, 8250.c and some other drivers in drivers/serial/ * * (C) Copyright 2010 Intel Corporation * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; version 2 * of the License. */ /* Notes: * 1. DMA channel allocation: 0/1 channel are assigned to port 0, * 2/3 chan to port 1, 4/5 chan to port 3. Even number chans * are used for RX, odd chans for TX * * 2. In A0 stepping, UART will not support TX half empty flag * * 3. The RI/DSR/DCD/DTR are not pinned out, DCD & DSR are always * asserted, only when the HW is reset the DDCD and DDSR will * be triggered */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define MFD_HSU_A0_STEPPING 1 #define HSU_DMA_BUF_SIZE 2048 #define chan_readl(chan, offset) readl(chan->reg + offset) #define chan_writel(chan, offset, val) writel(val, chan->reg + offset) #define mfd_readl(obj, offset) readl(obj->reg + offset) #define mfd_writel(obj, offset, val) writel(val, obj->reg + offset) #define HSU_DMA_TIMEOUT_CHECK_FREQ (HZ/10) struct hsu_dma_buffer { u8 *buf; dma_addr_t dma_addr; u32 dma_size; u32 ofs; }; struct hsu_dma_chan { u32 id; enum dma_data_direction dirt; struct uart_hsu_port *uport; void __iomem *reg; struct timer_list rx_timer; /* only needed by RX channel */ }; struct uart_hsu_port { struct uart_port port; unsigned char ier; unsigned char lcr; unsigned char mcr; unsigned int lsr_break_flag; char name[12]; int index; struct device *dev; struct hsu_dma_chan *txc; struct hsu_dma_chan *rxc; struct hsu_dma_buffer txbuf; struct hsu_dma_buffer rxbuf; int use_dma; /* flag for DMA/PIO */ int running; int dma_tx_on; }; /* Top level data structure of HSU */ struct hsu_port { void __iomem *reg; unsigned long paddr; unsigned long iolen; u32 irq; struct uart_hsu_port port[3]; struct hsu_dma_chan chans[10]; struct dentry *debugfs; }; static inline unsigned int serial_in(struct uart_hsu_port *up, int offset) { unsigned int val; if (offset > UART_MSR) { offset <<= 2; val = readl(up->port.membase + offset); } else val = (unsigned int)readb(up->port.membase + offset); return val; } static inline void serial_out(struct uart_hsu_port *up, int offset, int value) { if (offset > UART_MSR) { offset <<= 2; writel(value, up->port.membase + offset); } else { unsigned char val = value & 0xff; writeb(val, up->port.membase + offset); } } #ifdef CONFIG_DEBUG_FS #define HSU_REGS_BUFSIZE 1024 static int hsu_show_regs_open(struct inode *inode, struct file *file) { file->private_data = inode->i_private; return 0; } static ssize_t port_show_regs(struct file *file, char __user *user_buf, size_t count, loff_t *ppos) { struct uart_hsu_port *up = file->private_data; char *buf; u32 len = 0; ssize_t ret; buf = kzalloc(HSU_REGS_BUFSIZE, GFP_KERNEL); if (!buf) return 0; len += snprintf(buf + len, HSU_REGS_BUFSIZE - len, "MFD HSU port[%d] regs:\n", up->index); len += snprintf(buf + len, HSU_REGS_BUFSIZE - len, "=================================\n"); len += snprintf(buf + len, HSU_REGS_BUFSIZE - len, "IER: \t\t0x%08x\n", serial_in(up, UART_IER)); len += snprintf(buf + len, HSU_REGS_BUFSIZE - len, "IIR: \t\t0x%08x\n", serial_in(up, UART_IIR)); len += snprintf(buf + len, HSU_REGS_BUFSIZE - len, "LCR: \t\t0x%08x\n", serial_in(up, UART_LCR)); len += snprintf(buf + len, HSU_REGS_BUFSIZE - len, "MCR: \t\t0x%08x\n", serial_in(up, UART_MCR)); len += snprintf(buf + len, HSU_REGS_BUFSIZE - len, "LSR: \t\t0x%08x\n", serial_in(up, UART_LSR)); len += snprintf(buf + len, HSU_REGS_BUFSIZE - len, "MSR: \t\t0x%08x\n", serial_in(up, UART_MSR)); len += snprintf(buf + len, HSU_REGS_BUFSIZE - len, "FOR: \t\t0x%08x\n", serial_in(up, UART_FOR)); len += snprintf(buf + len, HSU_REGS_BUFSIZE - len, "PS: \t\t0x%08x\n", serial_in(up, UART_PS)); len += snprintf(buf + len, HSU_REGS_BUFSIZE - len, "MUL: \t\t0x%08x\n", serial_in(up, UART_MUL)); len += snprintf(buf + len, HSU_REGS_BUFSIZE - len, "DIV: \t\t0x%08x\n", serial_in(up, UART_DIV)); ret = simple_read_from_buffer(user_buf, count, ppos, buf, len); kfree(buf); return ret; } static ssize_t dma_show_regs(struct file *file, char __user *user_buf, size_t count, loff_t *ppos) { struct hsu_dma_chan *chan = file->private_data; char *buf; u32 len = 0; ssize_t ret; buf = kzalloc(HSU_REGS_BUFSIZE, GFP_KERNEL); if (!buf) return 0; len += snprintf(buf + len, HSU_REGS_BUFSIZE - len, "MFD HSU DMA channel [%d] regs:\n", chan->id); len += snprintf(buf + len, HSU_REGS_BUFSIZE - len, "=================================\n"); len += snprintf(buf + len, HSU_REGS_BUFSIZE - len, "CR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_CR)); len += snprintf(buf + len, HSU_REGS_BUFSIZE - len, "DCR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_DCR)); len += snprintf(buf + len, HSU_REGS_BUFSIZE - len, "BSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_BSR)); len += snprintf(buf + len, HSU_REGS_BUFSIZE - len, "MOTSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_MOTSR)); len += snprintf(buf + len, HSU_REGS_BUFSIZE - len, "D0SAR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D0SAR)); len += snprintf(buf + len, HSU_REGS_BUFSIZE - len, "D0TSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D0TSR)); len += snprintf(buf + len, HSU_REGS_BUFSIZE - len, "D0SAR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D1SAR)); len += snprintf(buf + len, HSU_REGS_BUFSIZE - len, "D0TSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D1TSR)); len += snprintf(buf + len, HSU_REGS_BUFSIZE - len, "D0SAR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D2SAR)); len += snprintf(buf + len, HSU_REGS_BUFSIZE - len, "D0TSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D2TSR)); len += snprintf(buf + len, HSU_REGS_BUFSIZE - len, "D0SAR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D3SAR)); len += snprintf(buf + len, HSU_REGS_BUFSIZE - len, "D0TSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D3TSR)); ret = simple_read_from_buffer(user_buf, count, ppos, buf, len); kfree(buf); return ret; } static const struct file_operations port_regs_ops = { .owner = THIS_MODULE, .open = hsu_show_regs_open, .read = port_show_regs, }; static const struct file_operations dma_regs_ops = { .owner = THIS_MODULE, .open = hsu_show_regs_open, .read = dma_show_regs, }; static int hsu_debugfs_init(struct hsu_port *hsu) { int i; char name[32]; hsu->debugfs = debugfs_create_dir("hsu", NULL); if (!hsu->debugfs) return -ENOMEM; for (i = 0; i < 3; i++) { snprintf(name, sizeof(name), "port_%d_regs", i); debugfs_create_file(name, S_IFREG | S_IRUGO, hsu->debugfs, (void *)(&hsu->port[i]), &port_regs_ops); } for (i = 0; i < 6; i++) { snprintf(name, sizeof(name), "dma_chan_%d_regs", i); debugfs_create_file(name, S_IFREG | S_IRUGO, hsu->debugfs, (void *)&hsu->chans[i], &dma_regs_ops); } return 0; } static void hsu_debugfs_remove(struct hsu_port *hsu) { if (hsu->debugfs) debugfs_remove_recursive(hsu->debugfs); } #else static inline int hsu_debugfs_init(struct hsu_port *hsu) { return 0; } static inline void hsu_debugfs_remove(struct hsu_port *hsu) { } #endif /* CONFIG_DEBUG_FS */ static void serial_hsu_enable_ms(struct uart_port *port) { struct uart_hsu_port *up = container_of(port, struct uart_hsu_port, port); up->ier |= UART_IER_MSI; serial_out(up, UART_IER, up->ier); } void hsu_dma_tx(struct uart_hsu_port *up) { struct circ_buf *xmit = &up->port.state->xmit; struct hsu_dma_buffer *dbuf = &up->txbuf; int count; /* test_and_set_bit may be better, but anyway it's in lock protected mode */ if (up->dma_tx_on) return; /* Update the circ buf info */ xmit->tail += dbuf->ofs; xmit->tail &= UART_XMIT_SIZE - 1; up->port.icount.tx += dbuf->ofs; dbuf->ofs = 0; /* Disable the channel */ chan_writel(up->txc, HSU_CH_CR, 0x0); if (!uart_circ_empty(xmit) && !uart_tx_stopped(&up->port)) { dma_sync_single_for_device(up->port.dev, dbuf->dma_addr, dbuf->dma_size, DMA_TO_DEVICE); count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE); dbuf->ofs = count; /* Reprogram the channel */ chan_writel(up->txc, HSU_CH_D0SAR, dbuf->dma_addr + xmit->tail); chan_writel(up->txc, HSU_CH_D0TSR, count); /* Reenable the channel */ chan_writel(up->txc, HSU_CH_DCR, 0x1 | (0x1 << 8) | (0x1 << 16) | (0x1 << 24)); up->dma_tx_on = 1; chan_writel(up->txc, HSU_CH_CR, 0x1); } if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) uart_write_wakeup(&up->port); } /* The buffer is already cache coherent */ void hsu_dma_start_rx_chan(struct hsu_dma_chan *rxc, struct hsu_dma_buffer *dbuf) { dbuf->ofs = 0; chan_writel(rxc, HSU_CH_BSR, 32); chan_writel(rxc, HSU_CH_MOTSR, 4); chan_writel(rxc, HSU_CH_D0SAR, dbuf->dma_addr); chan_writel(rxc, HSU_CH_D0TSR, dbuf->dma_size); chan_writel(rxc, HSU_CH_DCR, 0x1 | (0x1 << 8) | (0x1 << 16) | (0x1 << 24) /* timeout bit, see HSU Errata 1 */ ); chan_writel(rxc, HSU_CH_CR, 0x3); mod_timer(&rxc->rx_timer, jiffies + HSU_DMA_TIMEOUT_CHECK_FREQ); } /* Protected by spin_lock_irqsave(port->lock) */ static void serial_hsu_start_tx(struct uart_port *port) { struct uart_hsu_port *up = container_of(port, struct uart_hsu_port, port); if (up->use_dma) { hsu_dma_tx(up); } else if (!(up->ier & UART_IER_THRI)) { up->ier |= UART_IER_THRI; serial_out(up, UART_IER, up->ier); } } static void serial_hsu_stop_tx(struct uart_port *port) { struct uart_hsu_port *up = container_of(port, struct uart_hsu_port, port); struct hsu_dma_chan *txc = up->txc; if (up->use_dma) chan_writel(txc, HSU_CH_CR, 0x0); else if (up->ier & UART_IER_THRI) { up->ier &= ~UART_IER_THRI; serial_out(up, UART_IER, up->ier); } } /* This is always called in spinlock protected mode, so * modify timeout timer is safe here */ void hsu_dma_rx(struct uart_hsu_port *up, u32 int_sts) { struct hsu_dma_buffer *dbuf = &up->rxbuf; struct hsu_dma_chan *chan = up->rxc; struct uart_port *port = &up->port; struct tty_struct *tty = port->state->port.tty; int count; if (!tty) return; /* * First need to know how many is already transferred, * then check if its a timeout DMA irq, and return * the trail bytes out, push them up and reenable the * channel */ /* Timeout IRQ, need wait some time, see Errata 2 */ if (int_sts & 0xf00) udelay(2); /* Stop the channel */ chan_writel(chan, HSU_CH_CR, 0x0); count = chan_readl(chan, HSU_CH_D0SAR) - dbuf->dma_addr; if (!count) { /* Restart the channel before we leave */ chan_writel(chan, HSU_CH_CR, 0x3); return; } del_timer(&chan->rx_timer); dma_sync_single_for_cpu(port->dev, dbuf->dma_addr, dbuf->dma_size, DMA_FROM_DEVICE); /* * Head will only wrap around when we recycle * the DMA buffer, and when that happens, we * explicitly set tail to 0. So head will * always be greater than tail. */ tty_insert_flip_string(tty, dbuf->buf, count); port->icount.rx += count; dma_sync_single_for_device(up->port.dev, dbuf->dma_addr, dbuf->dma_size, DMA_FROM_DEVICE); /* Reprogram the channel */ chan_writel(chan, HSU_CH_D0SAR, dbuf->dma_addr); chan_writel(chan, HSU_CH_D0TSR, dbuf->dma_size); chan_writel(chan, HSU_CH_DCR, 0x1 | (0x1 << 8) | (0x1 << 16) | (0x1 << 24) /* timeout bit, see HSU Errata 1 */ ); tty_flip_buffer_push(tty); chan_writel(chan, HSU_CH_CR, 0x3); chan->rx_timer.expires = jiffies + HSU_DMA_TIMEOUT_CHECK_FREQ; add_timer(&chan->rx_timer); } static void serial_hsu_stop_rx(struct uart_port *port) { struct uart_hsu_port *up = container_of(port, struct uart_hsu_port, port); struct hsu_dma_chan *chan = up->rxc; if (up->use_dma) chan_writel(chan, HSU_CH_CR, 0x2); else { up->ier &= ~UART_IER_RLSI; up->port.read_status_mask &= ~UART_LSR_DR; serial_out(up, UART_IER, up->ier); } } static inline void receive_chars(struct uart_hsu_port *up, int *status) { struct tty_struct *tty = up->port.state->port.tty; unsigned int ch, flag; unsigned int max_count = 256; if (!tty) return; do { ch = serial_in(up, UART_RX); flag = TTY_NORMAL; up->port.icount.rx++; if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE | UART_LSR_FE | UART_LSR_OE))) { dev_warn(up->dev, "We really rush into ERR/BI case" "status = 0x%02x", *status); /* For statistics only */ if (*status & UART_LSR_BI) { *status &= ~(UART_LSR_FE | UART_LSR_PE); up->port.icount.brk++; /* * We do the SysRQ and SAK checking * here because otherwise the break * may get masked by ignore_status_mask * or read_status_mask. */ if (uart_handle_break(&up->port)) goto ignore_char; } else if (*status & UART_LSR_PE) up->port.icount.parity++; else if (*status & UART_LSR_FE) up->port.icount.frame++; if (*status & UART_LSR_OE) up->port.icount.overrun++; /* Mask off conditions which should be ignored. */ *status &= up->port.read_status_mask; #ifdef CONFIG_SERIAL_MFD_HSU_CONSOLE if (up->port.cons && up->port.cons->index == up->port.line) { /* Recover the break flag from console xmit */ *status |= up->lsr_break_flag; up->lsr_break_flag = 0; } #endif if (*status & UART_LSR_BI) { flag = TTY_BREAK; } else if (*status & UART_LSR_PE) flag = TTY_PARITY; else if (*status & UART_LSR_FE) flag = TTY_FRAME; } if (uart_handle_sysrq_char(&up->port, ch)) goto ignore_char; uart_insert_char(&up->port, *status, UART_LSR_OE, ch, flag); ignore_char: *status = serial_in(up, UART_LSR); } while ((*status & UART_LSR_DR) && max_count--); tty_flip_buffer_push(tty); } static void transmit_chars(struct uart_hsu_port *up) { struct circ_buf *xmit = &up->port.state->xmit; int count; if (up->port.x_char) { serial_out(up, UART_TX, up->port.x_char); up->port.icount.tx++; up->port.x_char = 0; return; } if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) { serial_hsu_stop_tx(&up->port); return; } #ifndef MFD_HSU_A0_STEPPING count = up->port.fifosize / 2; #else /* * A0 only supports fully empty IRQ, and the first char written * into it won't clear the EMPT bit, so we may need be cautious * by useing a shorter buffer */ count = up->port.fifosize - 4; #endif do { serial_out(up, UART_TX, xmit->buf[xmit->tail]); xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); up->port.icount.tx++; if (uart_circ_empty(xmit)) break; } while (--count > 0); if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) uart_write_wakeup(&up->port); if (uart_circ_empty(xmit)) serial_hsu_stop_tx(&up->port); } static inline void check_modem_status(struct uart_hsu_port *up) { int status; status = serial_in(up, UART_MSR); if ((status & UART_MSR_ANY_DELTA) == 0) return; if (status & UART_MSR_TERI) up->port.icount.rng++; if (status & UART_MSR_DDSR) up->port.icount.dsr++; /* We may only get DDCD when HW init and reset */ if (status & UART_MSR_DDCD) uart_handle_dcd_change(&up->port, status & UART_MSR_DCD); /* Will start/stop_tx accordingly */ if (status & UART_MSR_DCTS) uart_handle_cts_change(&up->port, status & UART_MSR_CTS); wake_up_interruptible(&up->port.state->port.delta_msr_wait); } /* * This handles the interrupt from one port. */ static irqreturn_t port_irq(int irq, void *dev_id) { struct uart_hsu_port *up = dev_id; unsigned int iir, lsr; unsigned long flags; if (unlikely(!up->running)) return IRQ_NONE; spin_lock_irqsave(&up->port.lock, flags); if (up->use_dma) { lsr = serial_in(up, UART_LSR); if (unlikely(lsr & (UART_LSR_BI | UART_LSR_PE | UART_LSR_FE | UART_LSR_OE))) dev_warn(up->dev, "Got lsr irq while using DMA, lsr = 0x%2x\n", lsr); check_modem_status(up); spin_unlock_irqrestore(&up->port.lock, flags); return IRQ_HANDLED; } iir = serial_in(up, UART_IIR); if (iir & UART_IIR_NO_INT) { spin_unlock_irqrestore(&up->port.lock, flags); return IRQ_NONE; } lsr = serial_in(up, UART_LSR); if (lsr & UART_LSR_DR) receive_chars(up, &lsr); check_modem_status(up); /* lsr will be renewed during the receive_chars */ if (lsr & UART_LSR_THRE) transmit_chars(up); spin_unlock_irqrestore(&up->port.lock, flags); return IRQ_HANDLED; } static inline void dma_chan_irq(struct hsu_dma_chan *chan) { struct uart_hsu_port *up = chan->uport; unsigned long flags; u32 int_sts; spin_lock_irqsave(&up->port.lock, flags); if (!up->use_dma || !up->running) goto exit; /* * No matter what situation, need read clear the IRQ status * There is a bug, see Errata 5, HSD 2900918 */ int_sts = chan_readl(chan, HSU_CH_SR); /* Rx channel */ if (chan->dirt == DMA_FROM_DEVICE) hsu_dma_rx(up, int_sts); /* Tx channel */ if (chan->dirt == DMA_TO_DEVICE) { chan_writel(chan, HSU_CH_CR, 0x0); up->dma_tx_on = 0; hsu_dma_tx(up); } exit: spin_unlock_irqrestore(&up->port.lock, flags); return; } static irqreturn_t dma_irq(int irq, void *dev_id) { struct hsu_port *hsu = dev_id; u32 int_sts, i; int_sts = mfd_readl(hsu, HSU_GBL_DMAISR); /* Currently we only have 6 channels may be used */ for (i = 0; i < 6; i++) { if (int_sts & 0x1) dma_chan_irq(&hsu->chans[i]); int_sts >>= 1; } return IRQ_HANDLED; } static unsigned int serial_hsu_tx_empty(struct uart_port *port) { struct uart_hsu_port *up = container_of(port, struct uart_hsu_port, port); unsigned long flags; unsigned int ret; spin_lock_irqsave(&up->port.lock, flags); ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0; spin_unlock_irqrestore(&up->port.lock, flags); return ret; } static unsigned int serial_hsu_get_mctrl(struct uart_port *port) { struct uart_hsu_port *up = container_of(port, struct uart_hsu_port, port); unsigned char status; unsigned int ret; status = serial_in(up, UART_MSR); ret = 0; if (status & UART_MSR_DCD) ret |= TIOCM_CAR; if (status & UART_MSR_RI) ret |= TIOCM_RNG; if (status & UART_MSR_DSR) ret |= TIOCM_DSR; if (status & UART_MSR_CTS) ret |= TIOCM_CTS; return ret; } static void serial_hsu_set_mctrl(struct uart_port *port, unsigned int mctrl) { struct uart_hsu_port *up = container_of(port, struct uart_hsu_port, port); unsigned char mcr = 0; if (mctrl & TIOCM_RTS) mcr |= UART_MCR_RTS; if (mctrl & TIOCM_DTR) mcr |= UART_MCR_DTR; if (mctrl & TIOCM_OUT1) mcr |= UART_MCR_OUT1; if (mctrl & TIOCM_OUT2) mcr |= UART_MCR_OUT2; if (mctrl & TIOCM_LOOP) mcr |= UART_MCR_LOOP; mcr |= up->mcr; serial_out(up, UART_MCR, mcr); } static void serial_hsu_break_ctl(struct uart_port *port, int break_state) { struct uart_hsu_port *up = container_of(port, struct uart_hsu_port, port); unsigned long flags; spin_lock_irqsave(&up->port.lock, flags); if (break_state == -1) up->lcr |= UART_LCR_SBC; else up->lcr &= ~UART_LCR_SBC; serial_out(up, UART_LCR, up->lcr); spin_unlock_irqrestore(&up->port.lock, flags); } /* * What special to do: * 1. chose the 64B fifo mode * 2. make sure not to select half empty mode for A0 stepping * 3. start dma or pio depends on configuration * 4. we only allocate dma memory when needed */ static int serial_hsu_startup(struct uart_port *port) { struct uart_hsu_port *up = container_of(port, struct uart_hsu_port, port); unsigned long flags; /* * Clear the FIFO buffers and disable them. * (they will be reenabled in set_termios()) */ serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO); serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT); serial_out(up, UART_FCR, 0); /* Clear the interrupt registers. */ (void) serial_in(up, UART_LSR); (void) serial_in(up, UART_RX); (void) serial_in(up, UART_IIR); (void) serial_in(up, UART_MSR); /* Now, initialize the UART, default is 8n1 */ serial_out(up, UART_LCR, UART_LCR_WLEN8); spin_lock_irqsave(&up->port.lock, flags); up->port.mctrl |= TIOCM_OUT2; serial_hsu_set_mctrl(&up->port, up->port.mctrl); /* * Finally, enable interrupts. Note: Modem status interrupts * are set via set_termios(), which will be occurring imminently * anyway, so we don't enable them here. */ if (!up->use_dma) up->ier = UART_IER_RLSI | UART_IER_RDI | UART_IER_RTOIE; else up->ier = 0; serial_out(up, UART_IER, up->ier); spin_unlock_irqrestore(&up->port.lock, flags); /* DMA init */ if (up->use_dma) { struct hsu_dma_buffer *dbuf; struct circ_buf *xmit = &port->state->xmit; up->dma_tx_on = 0; /* First allocate the RX buffer */ dbuf = &up->rxbuf; dbuf->buf = kzalloc(HSU_DMA_BUF_SIZE, GFP_KERNEL); if (!dbuf->buf) { up->use_dma = 0; goto exit; } dbuf->dma_addr = dma_map_single(port->dev, dbuf->buf, HSU_DMA_BUF_SIZE, DMA_FROM_DEVICE); dbuf->dma_size = HSU_DMA_BUF_SIZE; /* Start the RX channel right now */ hsu_dma_start_rx_chan(up->rxc, dbuf); /* Next init the TX DMA */ dbuf = &up->txbuf; dbuf->buf = xmit->buf; dbuf->dma_addr = dma_map_single(port->dev, dbuf->buf, UART_XMIT_SIZE, DMA_TO_DEVICE); dbuf->dma_size = UART_XMIT_SIZE; /* This should not be changed all around */ chan_writel(up->txc, HSU_CH_BSR, 32); chan_writel(up->txc, HSU_CH_MOTSR, 4); dbuf->ofs = 0; } exit: /* And clear the interrupt registers again for luck. */ (void) serial_in(up, UART_LSR); (void) serial_in(up, UART_RX); (void) serial_in(up, UART_IIR); (void) serial_in(up, UART_MSR); up->running = 1; return 0; } static void serial_hsu_shutdown(struct uart_port *port) { struct uart_hsu_port *up = container_of(port, struct uart_hsu_port, port); unsigned long flags; del_timer_sync(&up->rxc->rx_timer); /* Disable interrupts from this port */ up->ier = 0; serial_out(up, UART_IER, 0); up->running = 0; spin_lock_irqsave(&up->port.lock, flags); up->port.mctrl &= ~TIOCM_OUT2; serial_hsu_set_mctrl(&up->port, up->port.mctrl); spin_unlock_irqrestore(&up->port.lock, flags); /* Disable break condition and FIFOs */ serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC); serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT); serial_out(up, UART_FCR, 0); } static void serial_hsu_set_termios(struct uart_port *port, struct ktermios *termios, struct ktermios *old) { struct uart_hsu_port *up = container_of(port, struct uart_hsu_port, port); struct tty_struct *tty = port->state->port.tty; unsigned char cval, fcr = 0; unsigned long flags; unsigned int baud, quot; u32 ps, mul; switch (termios->c_cflag & CSIZE) { case CS5: cval = UART_LCR_WLEN5; break; case CS6: cval = UART_LCR_WLEN6; break; case CS7: cval = UART_LCR_WLEN7; break; default: case CS8: cval = UART_LCR_WLEN8; break; } /* CMSPAR isn't supported by this driver */ if (tty) tty->termios->c_cflag &= ~CMSPAR; if (termios->c_cflag & CSTOPB) cval |= UART_LCR_STOP; if (termios->c_cflag & PARENB) cval |= UART_LCR_PARITY; if (!(termios->c_cflag & PARODD)) cval |= UART_LCR_EPAR; /* * For those basic low baud rate we can get the direct * scalar from 2746800, like 115200 = 2746800/24, for those * higher baud rate, we have to handle them case by case, * but DIV reg is never touched as its default value 0x3d09 */ baud = uart_get_baud_rate(port, termios, old, 0, 4000000); quot = uart_get_divisor(port, baud); switch (baud) { case 3500000: mul = 0x3345; ps = 0xC; quot = 1; break; case 18432000: mul = 0x2400; ps = 0x10; quot = 1; break; case 3000000: case 2500000: case 2000000: case 1500000: case 1000000: case 500000: /* mul/ps/quot = 0x9C4/0x10/0x1 will make a 500000 bps */ mul = baud / 500000 * 0x9C4; break; default: ; } if ((up->port.uartclk / quot) < (2400 * 16)) fcr = UART_FCR_ENABLE_FIFO | UART_FCR_HSU_64_1B; else if ((up->port.uartclk / quot) < (230400 * 16)) fcr = UART_FCR_ENABLE_FIFO | UART_FCR_HSU_64_16B; else fcr = UART_FCR_ENABLE_FIFO | UART_FCR_HSU_64_32B; fcr |= UART_FCR_HSU_64B_FIFO; #ifdef MFD_HSU_A0_STEPPING /* A0 doesn't support half empty IRQ */ fcr |= UART_FCR_FULL_EMPT_TXI; #endif /* * Ok, we're now changing the port state. Do it with * interrupts disabled. */ spin_lock_irqsave(&up->port.lock, flags); /* Update the per-port timeout */ uart_update_timeout(port, termios->c_cflag, baud); up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR; if (termios->c_iflag & INPCK) up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE; if (termios->c_iflag & (BRKINT | PARMRK)) up->port.read_status_mask |= UART_LSR_BI; /* Characters to ignore */ up->port.ignore_status_mask = 0; if (termios->c_iflag & IGNPAR) up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE; if (termios->c_iflag & IGNBRK) { up->port.ignore_status_mask |= UART_LSR_BI; /* * If we're ignoring parity and break indicators, * ignore overruns too (for real raw support). */ if (termios->c_iflag & IGNPAR) up->port.ignore_status_mask |= UART_LSR_OE; } /* Ignore all characters if CREAD is not set */ if ((termios->c_cflag & CREAD) == 0) up->port.ignore_status_mask |= UART_LSR_DR; /* * CTS flow control flag and modem status interrupts, disable * MSI by default */ up->ier &= ~UART_IER_MSI; if (UART_ENABLE_MS(&up->port, termios->c_cflag)) up->ier |= UART_IER_MSI; serial_out(up, UART_IER, up->ier); if (termios->c_cflag & CRTSCTS) up->mcr |= UART_MCR_AFE | UART_MCR_RTS; else up->mcr &= ~UART_MCR_AFE; serial_out(up, UART_LCR, cval | UART_LCR_DLAB); /* set DLAB */ serial_out(up, UART_DLL, quot & 0xff); /* LS of divisor */ serial_out(up, UART_DLM, quot >> 8); /* MS of divisor */ serial_out(up, UART_LCR, cval); /* reset DLAB */ serial_out(up, UART_MUL, mul); /* set MUL */ serial_out(up, UART_PS, ps); /* set PS */ up->lcr = cval; /* Save LCR */ serial_hsu_set_mctrl(&up->port, up->port.mctrl); serial_out(up, UART_FCR, fcr); spin_unlock_irqrestore(&up->port.lock, flags); } static void serial_hsu_pm(struct uart_port *port, unsigned int state, unsigned int oldstate) { } static void serial_hsu_release_port(struct uart_port *port) { } static int serial_hsu_request_port(struct uart_port *port) { return 0; } static void serial_hsu_config_port(struct uart_port *port, int flags) { struct uart_hsu_port *up = container_of(port, struct uart_hsu_port, port); up->port.type = PORT_MFD; } static int serial_hsu_verify_port(struct uart_port *port, struct serial_struct *ser) { /* We don't want the core code to modify any port params */ return -EINVAL; } static const char * serial_hsu_type(struct uart_port *port) { struct uart_hsu_port *up = container_of(port, struct uart_hsu_port, port); return up->name; } /* Mainly for uart console use */ static struct uart_hsu_port *serial_hsu_ports[3]; static struct uart_driver serial_hsu_reg; #ifdef CONFIG_SERIAL_MFD_HSU_CONSOLE #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE) /* Wait for transmitter & holding register to empty */ static inline void wait_for_xmitr(struct uart_hsu_port *up) { unsigned int status, tmout = 1000; /* Wait up to 1ms for the character to be sent. */ do { status = serial_in(up, UART_LSR); if (status & UART_LSR_BI) up->lsr_break_flag = UART_LSR_BI; if (--tmout == 0) break; udelay(1); } while (!(status & BOTH_EMPTY)); /* Wait up to 1s for flow control if necessary */ if (up->port.flags & UPF_CONS_FLOW) { tmout = 1000000; while (--tmout && ((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0)) udelay(1); } } static void serial_hsu_console_putchar(struct uart_port *port, int ch) { struct uart_hsu_port *up = container_of(port, struct uart_hsu_port, port); wait_for_xmitr(up); serial_out(up, UART_TX, ch); } /* * Print a string to the serial port trying not to disturb * any possible real use of the port... * * The console_lock must be held when we get here. */ static void serial_hsu_console_write(struct console *co, const char *s, unsigned int count) { struct uart_hsu_port *up = serial_hsu_ports[co->index]; unsigned long flags; unsigned int ier; int locked = 1; local_irq_save(flags); if (up->port.sysrq) locked = 0; else if (oops_in_progress) { locked = spin_trylock(&up->port.lock); } else spin_lock(&up->port.lock); /* First save the IER then disable the interrupts */ ier = serial_in(up, UART_IER); serial_out(up, UART_IER, 0); uart_console_write(&up->port, s, count, serial_hsu_console_putchar); /* * Finally, wait for transmitter to become empty * and restore the IER */ wait_for_xmitr(up); serial_out(up, UART_IER, ier); if (locked) spin_unlock(&up->port.lock); local_irq_restore(flags); } static struct console serial_hsu_console; static int __init serial_hsu_console_setup(struct console *co, char *options) { struct uart_hsu_port *up; int baud = 115200; int bits = 8; int parity = 'n'; int flow = 'n'; int ret; if (co->index == -1 || co->index >= serial_hsu_reg.nr) co->index = 0; up = serial_hsu_ports[co->index]; if (!up) return -ENODEV; if (options) uart_parse_options(options, &baud, &parity, &bits, &flow); ret = uart_set_options(&up->port, co, baud, parity, bits, flow); return ret; } static struct console serial_hsu_console = { .name = "ttyMFD", .write = serial_hsu_console_write, .device = uart_console_device, .setup = serial_hsu_console_setup, .flags = CON_PRINTBUFFER, .index = 2, .data = &serial_hsu_reg, }; #endif struct uart_ops serial_hsu_pops = { .tx_empty = serial_hsu_tx_empty, .set_mctrl = serial_hsu_set_mctrl, .get_mctrl = serial_hsu_get_mctrl, .stop_tx = serial_hsu_stop_tx, .start_tx = serial_hsu_start_tx, .stop_rx = serial_hsu_stop_rx, .enable_ms = serial_hsu_enable_ms, .break_ctl = serial_hsu_break_ctl, .startup = serial_hsu_startup, .shutdown = serial_hsu_shutdown, .set_termios = serial_hsu_set_termios, .pm = serial_hsu_pm, .type = serial_hsu_type, .release_port = serial_hsu_release_port, .request_port = serial_hsu_request_port, .config_port = serial_hsu_config_port, .verify_port = serial_hsu_verify_port, }; static struct uart_driver serial_hsu_reg = { .owner = THIS_MODULE, .driver_name = "MFD serial", .dev_name = "ttyMFD", .major = TTY_MAJOR, .minor = 128, .nr = 3, }; #ifdef CONFIG_PM static int serial_hsu_suspend(struct pci_dev *pdev, pm_message_t state) { void *priv = pci_get_drvdata(pdev); struct uart_hsu_port *up; /* Make sure this is not the internal dma controller */ if (priv && (pdev->device != 0x081E)) { up = priv; uart_suspend_port(&serial_hsu_reg, &up->port); } pci_save_state(pdev); pci_set_power_state(pdev, pci_choose_state(pdev, state)); return 0; } static int serial_hsu_resume(struct pci_dev *pdev) { void *priv = pci_get_drvdata(pdev); struct uart_hsu_port *up; int ret; pci_set_power_state(pdev, PCI_D0); pci_restore_state(pdev); ret = pci_enable_device(pdev); if (ret) dev_warn(&pdev->dev, "HSU: can't re-enable device, try to continue\n"); if (priv && (pdev->device != 0x081E)) { up = priv; uart_resume_port(&serial_hsu_reg, &up->port); } return 0; } #else #define serial_hsu_suspend NULL #define serial_hsu_resume NULL #endif /* temp global pointer before we settle down on using one or four PCI dev */ static struct hsu_port *phsu; static int serial_hsu_probe(struct pci_dev *pdev, const struct pci_device_id *ent) { struct uart_hsu_port *uport; int index, ret; printk(KERN_INFO "HSU: found PCI Serial controller(ID: %04x:%04x)\n", pdev->vendor, pdev->device); switch (pdev->device) { case 0x081B: index = 0; break; case 0x081C: index = 1; break; case 0x081D: index = 2; break; case 0x081E: /* internal DMA controller */ index = 3; break; default: dev_err(&pdev->dev, "HSU: out of index!"); return -ENODEV; } ret = pci_enable_device(pdev); if (ret) return ret; if (index == 3) { /* DMA controller */ ret = request_irq(pdev->irq, dma_irq, 0, "hsu_dma", phsu); if (ret) { dev_err(&pdev->dev, "can not get IRQ\n"); goto err_disable; } pci_set_drvdata(pdev, phsu); } else { /* UART port 0~2 */ uport = &phsu->port[index]; uport->port.irq = pdev->irq; uport->port.dev = &pdev->dev; uport->dev = &pdev->dev; ret = request_irq(pdev->irq, port_irq, 0, uport->name, uport); if (ret) { dev_err(&pdev->dev, "can not get IRQ\n"); goto err_disable; } uart_add_one_port(&serial_hsu_reg, &uport->port); #ifdef CONFIG_SERIAL_MFD_HSU_CONSOLE if (index == 2) { register_console(&serial_hsu_console); uport->port.cons = &serial_hsu_console; } #endif pci_set_drvdata(pdev, uport); } return 0; err_disable: pci_disable_device(pdev); return ret; } static void hsu_dma_rx_timeout(unsigned long data) { struct hsu_dma_chan *chan = (void *)data; struct uart_hsu_port *up = chan->uport; struct hsu_dma_buffer *dbuf = &up->rxbuf; int count = 0; unsigned long flags; spin_lock_irqsave(&up->port.lock, flags); count = chan_readl(chan, HSU_CH_D0SAR) - dbuf->dma_addr; if (!count) { mod_timer(&chan->rx_timer, jiffies + HSU_DMA_TIMEOUT_CHECK_FREQ); goto exit; } hsu_dma_rx(up, 0); exit: spin_unlock_irqrestore(&up->port.lock, flags); } static void hsu_global_init(void) { struct hsu_port *hsu; struct uart_hsu_port *uport; struct hsu_dma_chan *dchan; int i, ret; hsu = kzalloc(sizeof(struct hsu_port), GFP_KERNEL); if (!hsu) return; /* Get basic io resource and map it */ hsu->paddr = 0xffa28000; hsu->iolen = 0x1000; if (!(request_mem_region(hsu->paddr, hsu->iolen, "HSU global"))) pr_warning("HSU: error in request mem region\n"); hsu->reg = ioremap_nocache((unsigned long)hsu->paddr, hsu->iolen); if (!hsu->reg) { pr_err("HSU: error in ioremap\n"); ret = -ENOMEM; goto err_free_region; } /* Initialise the 3 UART ports */ uport = hsu->port; for (i = 0; i < 3; i++) { uport->port.type = PORT_MFD; uport->port.iotype = UPIO_MEM; uport->port.mapbase = (resource_size_t)hsu->paddr + HSU_PORT_REG_OFFSET + i * HSU_PORT_REG_LENGTH; uport->port.membase = hsu->reg + HSU_PORT_REG_OFFSET + i * HSU_PORT_REG_LENGTH; sprintf(uport->name, "hsu_port%d", i); uport->port.fifosize = 64; uport->port.ops = &serial_hsu_pops; uport->port.line = i; uport->port.flags = UPF_IOREMAP; /* set the scalable maxim support rate to 2746800 bps */ uport->port.uartclk = 115200 * 24 * 16; uport->running = 0; uport->txc = &hsu->chans[i * 2]; uport->rxc = &hsu->chans[i * 2 + 1]; serial_hsu_ports[i] = uport; uport->index = i; uport++; } /* Initialise 6 dma channels */ dchan = hsu->chans; for (i = 0; i < 6; i++) { dchan->id = i; dchan->dirt = (i & 0x1) ? DMA_FROM_DEVICE : DMA_TO_DEVICE; dchan->uport = &hsu->port[i/2]; dchan->reg = hsu->reg + HSU_DMA_CHANS_REG_OFFSET + i * HSU_DMA_CHANS_REG_LENGTH; /* Work around for RX */ if (dchan->dirt == DMA_FROM_DEVICE) { init_timer(&dchan->rx_timer); dchan->rx_timer.function = hsu_dma_rx_timeout; dchan->rx_timer.data = (unsigned long)dchan; } dchan++; } phsu = hsu; hsu_debugfs_init(hsu); return; err_free_region: release_mem_region(hsu->paddr, hsu->iolen); kfree(hsu); return; } static void serial_hsu_remove(struct pci_dev *pdev) { void *priv = pci_get_drvdata(pdev); struct uart_hsu_port *up; if (!priv) return; /* For port 0/1/2, priv is the address of uart_hsu_port */ if (pdev->device != 0x081E) { up = priv; uart_remove_one_port(&serial_hsu_reg, &up->port); } pci_set_drvdata(pdev, NULL); free_irq(pdev->irq, priv); pci_disable_device(pdev); } /* First 3 are UART ports, and the 4th is the DMA */ static const struct pci_device_id pci_ids[] __devinitdata = { { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081B) }, { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081C) }, { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081D) }, { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081E) }, {}, }; static struct pci_driver hsu_pci_driver = { .name = "HSU serial", .id_table = pci_ids, .probe = serial_hsu_probe, .remove = __devexit_p(serial_hsu_remove), .suspend = serial_hsu_suspend, .resume = serial_hsu_resume, }; static int __init hsu_pci_init(void) { int ret; hsu_global_init(); ret = uart_register_driver(&serial_hsu_reg); if (ret) return ret; return pci_register_driver(&hsu_pci_driver); } static void __exit hsu_pci_exit(void) { pci_unregister_driver(&hsu_pci_driver); uart_unregister_driver(&serial_hsu_reg); hsu_debugfs_remove(phsu); kfree(phsu); } module_init(hsu_pci_init); module_exit(hsu_pci_exit); MODULE_LICENSE("GPL v2"); MODULE_ALIAS("platform:medfield-hsu");